Fix ABS / ESC warning light C0020:1C on Mazda5 2010 UK (or Mazda3)

Hi Everyone especially the mazda5 / mazda3 owners I want to share this for I think our 5s deserve longer time in service rather than going into scrap yard sadly. How can you find the 7-seater today which combines the manual, NA engine, sliding open door, practicality, beauty, and driving pleasure (yes I think it has) today when everybody are ONLY making or buying boring SUVs?

This error code happens on the vehicle affected by, as detailed by the SB-10097406-2532, the design defect in ABS module: pump motor brush having poor contact. It happens on my car every time it drives after 30min (so the temperature in the engine chamber is high) and the error code clears after I parked it overnighto_O

To my experience, garages in UK here don't really want to work on this job (maybe only because I live in a metropolitan area like Manchester) and they prefer other easy job which also makes profit. What they would do is to remove the old module and send it to a 'specialist' to re-work or fix it, but this will take weeks when I can't use the car! Obviously using a replacement module I can find on Ebay is not even an option to them. Maybe it's just the insane labour hours it can take - the ford C-platform seem to have put the ABS module at a EXTREMELY inconvenient position behind the battery box. No surprise the problematic module is again produced by ford :ROFLMAO:

Anyway, to my experience, you can definitely resolve this issue by yourself before it fails your car for MOT / annual inspection / whatever 'road legal' requirement.
All you need are the following:

1. a ****-437AZ-B ABS module. I have verified using BFD4-437AZ-B from a 12' mazda3 to replace the original C513-437AZ-A on my 5. (the "-A" production batch has the issue, obviously). I 90% sure you can use whatever ***-437AZ-B, ***-437AZ-C or even -D module you can find on Ebay, no matter it comes from a ford, or from a diesel model. This saves me 100+ GBP for a c513-437az-b on Ebay will be ~200GBP but what I bought was only 50.

(One more tip: actually you can, after removing the battery & battery box and getting access to the module on your car, plug in the new module you've bought, connect the battery with jump-start wire to power-up your car, and then check if any ABS / ESC warning light and error code. If all green, then you are 99% sure the module you buy will work)

2. a scanner tool, ideally forscan, to do the job just in case you ever need re-programming the ABS module. (On youtube there is a video about re-programming ABS AS-built data - I guess that's on a ford car). I have bought a Vlinker FS OBD-USB cable for using for forscan. It turned out I actually didn't need to do so.

3. time. I took 2+ hours removing the module, another 2+ hours to install the new one. Yet 2 more hour to do a not-so-bad brake bleeding to make sure I can drive my car to a garage for 'proper' brake bleeding.

4. carefulness and a lot of grease in your arm and back. As I said the ABS module is at a position which is f***king stupid. Again you need to be careful not to damage the brake line or the screw / screw thread.

5. tools. There are better tools I think for un-tighten / tighten the brake line screws, as agaaaaaaaain the module is in a very in-convenient position. Anyway I used a flare nut 10mm wrench with "flexible" head. (you definitely need a flare nut wrench to avoid brake line damage.) The wrench ideally has a longer arm, for the screws are fairly tight.

6. for brake bleeding, the bleeder screw on the Mazda5 I have is 10mm at the rear and 9mm at the front (how did the engineers lost their mind?)

Good luck if you decide to work on it and save you Mazda. It's better if you have a trusted local garage as plan-B... I took months explaining to myself this has a good chance to work:ROFLMAO:

P.S. for those in UK, my mazda5 is a 60 reg, 2.0 DISI engine with i-stop.
 
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